#!/usr/bin/python
# -*- coding: UTF-8 -*-

# with open('test.txt', 'r') as f:
#     for line in f:
#         print(line)

# with open('test.txt', 'w') as f:
#     f.write('Hello, world!\n')
#     f.write('This is a test file.\n')

# with open('test.txt', 'a') as f:
#     f.write('This is the end of the file.\n')